It sounds like your tank was taking unreasonable damage because I don't consider that a hard-hitting dungeon. Potions won't help them much but gear and getting out of AoEs will. CC does have some confusing mechanics for newbies but that's about it. During the princess she hits so softly that Regen should keep up the tank, and you don't need tricks to kite the adds, just run big circles and dont stop, if you stop you die.

Second boss has it's hectic moments but you get use to it. Chimera at the end can cause problems. Some words will appear on screen "Violet Eyes" -- stack on boss. "Blue Eyes" -- run away, and it helps if you can be aware of what the tank and DPS are doing so you can precast heals on the ones that missed the mechanic. If there's an Orb coming at you, just kite it away.

The adds aren't anything special, just be careful around the bombs. It's not unusual for my tanks to pull several groups in there, it's not too bad to heal through but it's up to you and the tank what's manageable.